1. Field of the Invention
This invention relates to a two-phase aqueous laundry pre-spotting composition. More particularly, this invention relates to a two-phase aqueous emulsion pre-spotting composition containing a relatively low amount of solvent having superior cleaning and stain removal properties. Specifically, this invention relates to an aqueous anionic two-phase pre-spotter composition having a clear upper phase and a cloudy lower phase. The emulsion, when in proper form, is a water-in-oil, and just approaching an oil-in-water composition, whereby both water-borne and oil-borne stains are removed.
Currently, commercially available pre-spotting compositions fall into two main categories: aqueous-based and solvent-based. The aqueous-based pre-spotting compositions are primarily non-aerosol formulations dispensed from trigger spray bottles or squeeze bottles onto the fabric before they are laundered. Typically, aqueous-based pre-spotting compositions have good stain removal against so-called "water-borne" stains. These stains include a variety of stains such as grape juice, mustard, grass, chocolate, clay, and similar stains.
The solvent-based formulations typically have been packaged in aerosol form. The solvent-based pre-spotting compositions typically are more effective in removing "oil-borne" stains such as cooking oil, fat, sebum, grease, motor oil and the like. Solvent-based pre-spotting compositions can be formulated with adequate water-borne stain removal. However, it is desirable to utilize an emulsion containing both solvents and water so as to be able to attack both water-borne and oil-borne stains.
Lately, because of the increased cost of various solvents utilized in solvent-based pre-spotters, there has been great emphasis on lessening the amount of solvent utilized and replacing this with other less expensive components, such as water. In addition, it has been desirable to prepare a pre-spotting composition which contains a high degree of water and yet will attack both water-borne and oil-borne stains on laundry fabrics.
Brusky, et al., U.S. Pat. No. 4,438,009, discloses a water-in-oil detergent emulsion for use as a detergent pre-spotting composition. The composition of Brusky contains a sorbitan nonionic surfactant as a stabilizer for the system, as well as other nonionic surfactants which aid in the removal of those oil-borne and water-borne stains and utilizes a relatively low amount of solvent in addition to the mixture of nonionic surfactants. The present invention differs from Brusky, et al., in that the present invention is an oil-out/just approaching a water-out formulation containing anionic surfactants, as well as a number of other ingredients. Accordingly, the present invention differs from and is an improvement over the Brusky, et al., disclosure.
Mitchell, et al., U.S. Pat. No. 4,180,472, discloses an oily-soil-dissolving agent consisting essentially of a water-insoluble solvent, a water-in-oil emulsifiable solvent, and water with other detergent builders. The Mitchell disclosure depends upon a two part treatment wherein the user first places a solvent having an anionic surfactant on the article to be laundered, and then, in a separate step, adds a water anionic system to remove the solvent residual. The present invention accomplishes these twin aims in a single application. Furthermore, there is no mention in the Mitchell disclosure of creating a composition having an HLB such that the composition, as a whole, is at the water-out/oil-out phase inversion point. Accordingly, the present invention differs greatly from and is an improvement over Mitchell, et al.
Wise, et al., U.S. Pat. No. 4,176,080, discloses a detergent composition similar to the Mitchell disclosure. The Wise disclosure employs a sequential treatment of fabrics in an aqueous washing medium with first, a water-insoluble solvent, and second, a composition comprising a water-soluble surfactant with an HLB of about 11-18.
The present invention differs from Wise, et al., in that Wise is limited only to the removal of oil-borne stains and exceeds the low solvent amounts of the present invention. Accordingly, the present invention differs from and is an improvement over Wise, et al.
Ramachandran, U.S. Pat. No. 3,915,633 relates to a pre-wash composition adapted to be sprayed on a soiled fabric before washing. The composition consists of an organic complexing acid, a surfactant, and water.
Ramachandran does not disclose the use of a sodium hydroxide, a free acid form of a complex organic phosphate ester, an isoparaffinic solvent or d-Limonene in a pre-wash composition. Further, the composition of Ramachandran is not in the form of an emulsion and does not utilize anionic surfactants. Accordingly, the present invention differs from and is an improvement over Ramachandran.